However, Anthony Harper lawyer Peter Woods, whose firm has represented about 200 claimants against EQC and insurers, said that was an "outrageous statement".

"EQC knows that the work has been botched. They know that the assessments were inadequate and they know that the work was botched and to say it was actually subsequent damage is far-fetched," Mr Woods said.

Mr Woods said he believed that was the first time such an assertion had been made and his clients would be really disappointed by it.

He said the comment was also inconsistent with how EQC had approached the failed repairs.

"It has not said, 'actually, this was subsequent earthquake damage and we'll open a new claim for you'. It's just treated them as botched repairs and botched assessments, which is what they were."

Colin Ashby, a structural engineer who had been working in Christchurch since September 2010, said any damage from subsequent earthquakes would be minor.

"You'd get a crack that would have been repaired and it would have opened up again. There may have been a little bit of settlement but nothing like the major earthquakes."

The work should instead have improved the homes, Mr Ashby said.

"Theoretically they should have been better than they were before the major earthquakes."

Lester Bryant from Asset Sure Quantity Surveyors, who has represented hundreds of owners in insurance claims, said millions of dollars had been wasted on repairs to quake-damaged homes because the damage was never diagnosed properly.

He said bad scoping was at the foundation of almost all the problems.

He knew of some properties that had been repaired twice but were still failing because the real damage was never identified in the first place.

Homeowners who accepted cash settlements had since discovered the true cost of the work is much more but they are unable to seek legal redress, he said.

'Call-backs'

Mr Brownlee has also suggested that the number of "call-backs" to properties by contractors was low compared with others in the building industry.

"If you look at the total cost of the EQC repair bill down here and then you look at what percentage that presents on a call-back basis, and then compare that to call-backs on a brand new build, and it's still very low," Mr Brownlee said

But Peter Woods said that was far fetched and disingenuous.

He pointed to figures released yesterday by the Minister Responsible for the Earthquake Commission, Megan Woods, which indicated that out of 67,747 managed repairs, 13,993 - or about 20 percent of them - had resulted in a call back.

"I think that's appalling that 20 percent of the homes have had to be re-repaired or perhaps re-re-repaired. And we know that there's thousands more out there that haven't been sorted out yet."

It amounted to a 20 percent failure rate by EQC, Mr Woods said.

"I would say if EQC was a building company, it would have gone bust years ago. Twenty percent of the work, of the homes it touched, it had to go back. It would have gone bust. Certainly there would not have been any word of mouth referrals from customers suggesting that people should use EQC as a contractor."

Mr Brownlee said his government had met their obligations to homeowners.

"The government never walked away from Christchurch."

Peter Woods said he had no evidence to suggest the National government had walked away and he believed EQC had responded well after the September 2010 earthquake.

However he said he believed that changed in February 2011 when EQC figured out that it would not have enough money.

EQC confirmed that staff numbers at its Christchurch office dropped from 389 in September 2016 to 285 by November 2017. It said the decrease reflected that the Commission had completed first time repairs and was focused on settling remedial claims.

Mr Woods said this drop occurred even though the amount of work to be done was increasing, he said.

There was a drop in staff numbers over successive years, even though the amount of work to be done was increasing, he said.

"That doesn't match with what Mr Brownlee's saying was the previous government's approach."

EQC appeared to adopt a strategy to do the least amount of work, he said.

"It appears from the outside there was a drive for cost cutting and for doing assessments and repairs as cheaply and once over lightly as possible."

Solo mum Tania Ashton is warning people not to buy houses repaired by EQC, after discovering the home she bought needs repairs costing hundreds of thousands of dollars, which insurance won't cover. Video, Audio

EQC CEO Sid Miller says the agency is currently defending 316 legal cases over the Christchurch earthquakes, and is considering legal action against Fletcher's for its project management of the… Video, Audio